#include<stdio.h>
#include<algorithm>
using namespace std;
bool cmp(int x,int y)
{    return x>y;
}
int main()
{    int t,n,i,sum;
    int a[20005];
    scanf("%d",&t);
    while(t--)
    {    scanf("%d",&n);sum=0;
        for(i=1;i<=n;i++)
        {    scanf("%d",&a[i]);
        }
        sort(a+1,a+n+1,cmp);
        for(i=3;i<=n;i+=3)
        {    sum+=a[i];
        }
        printf("%d\n",sum);
    }
    return 0;
}